Synonyms for Poisonous substance:

• n.

  •poison (noun)
  • poison.
  •toxin (noun)
  • contagion,
  • venom,
  • germ,
  • blight,
  • cancer,
  • infection,
  • virus,
  • contamination.

• Other synonyms:

  •Other relevant words:
  • toxicant.